Air Conditioning and Heating System

ABSTRACT

An air conditioning/heating system that distributes, through a closed loop water circulating system, cold or hot water to one or more separate air handlers that are connected to a central water chiller/heat pump by supply and return lines for each handler. The system includes a cabinet, an insulated tank within the cabinet, a main coil within the tank, the main coil having a recirculation line with a water inlet and a water outlet, and a refrigerant line attached to the recirculation line; a heat pump/condensing unit connected to the refrigerant line, a circulating pump having a pump inlet and a pump outlet, the pump outlet connected to the water inlet of the main coil, a second tank connected to the pump inlet; at least one air handler having a box, a blower within the box, and a secondary coil within the box, the secondary coil having a supply inlet connected to the outlet of the first coil and a return outlet connected to the second tank.

This application claims the benefit of U.S. provisional patent application No. 62/430,691.

CROSS REFERENCES TO RELATED APPLICATIONS

Not applicable.

FEDERALLY SPONSORED RESEARCH

Not applicable.

BACKGROUND OF THE INVENTION 1. Field of the Invention

This invention relates generally to environmental control devices. More specifically, the invention relates to an air conditioning/heating system that spatially separates the air handlers from the central chiller/heating unit.

2. Description of the Related Art

Typical air condition systems use vapor-compression or absorption refrigeration cycles. In these systems, a circulating refrigerant absorbs and removes heat from the space to be cooled and then subsequently rejects the heat elsewhere. All such systems include a compressor, a condenser, a thermal expansion valve, and an evaporator connected together by copper/high pressure lines. Because of the need for each of these components, these types of systems are not easily portable.

While portable cooling/heating systems are known, they suffer from a number of deficiencies. For one, they are often evaporative coolers that cool air through the evaporation of water. The increased moisture and humidity resulting from evaporation promotes rust forming on machinery and tools in work spaces. They use a large amount of cooling water, are not comfortable in humid areas, and do not heat. Other systems combine the air handler in the same housing as the compressor, which requires both to be moved, generates undesirable noise at the location where cooling is desired, requires excessive cooling water for the condenser to be dumped somewhere or the system absorbs and reject heat into the same space, and can create adverse temperatures in that space surrounding the system.

SUMMARY OF THE INVENTION

The present invention is an air conditioning/heating system that provides “spot” air to work or entertainment spaces while inhibiting rust formation on the machinery and tools in the work spaces, and not requiring large expensive air conditioning/heating units and duct work. The invention also reduces noise at the cooling/heating location relative to existing systems. Open air shops can have personnel or equipment be heated or cooled with dehumidified air, thereby creating a temperature controlled space for multiple separate work or entertainment areas. The air handlers may be easily moved about and can be placed in the space to be heated or cooled, and the volume of air produced is controlled by the air volume control. The noise of the mechanics of producing air conditioning or heating is confined to the central chiller unit.

The system includes a cabinet, an insulated tank within the cabinet, a main coil within the tank, the main coil having a recirculation line with a water inlet and a water outlet, and a refrigerant line attached to the recirculation line; a heat pump/condensing unit connected to the refrigerant line, a circulating pump having a pump inlet and a pump outlet, the pump outlet connected to the water inlet of the main coil, a second tank connected to the pump inlet; at least one air handler having a box, a blower within the box, and a secondary coil within the box, the secondary coil having a supply inlet connected to the outlet of the first coil and a return outlet connected to the second tank.

The system is up to 85% more efficient than traditional chillers by allowing the refrigeration unit to continue to run at its highest efficiency and highest capacity for its entire run cycle without offloading up to 85% of its capacity by means of traditional unloading devices, such as hot gas/by pass valves. For example, during periods of light load, only one “zone,” or air handler, is being used with air volume from the air handler turned down to remove only a half-ton of energy. The refrigeration unit is not only removing the heat (or adding heat when the system is in heating mode) from the recirculating water line within the energy storage take, but it is removing energy (or adding energy when the system is in heating mode) from the water within the energy storage tank for later use. Once the energy storage tank reaches its set point (e.g., 40° F. for cooling/120° F. for heating), the refrigeration unit cycles off allowing the cooling/heating to be provided by a volume of water within the energy storage tank as the system continues to absorb/reject energy from the previous run cycle.

The system recirculates the water through the closed loop water system, thereby reducing the amount of fresh water needed during the operation. The system also uses water instead of a glycol mixture. The system is therefore more environmentally friendly and cost efficient than the closest prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a system diagram of an embodiment of the present invention.

FIG. 2 is a sectional view showing the cross sectional profile of a portion of the coil body through line 2-2 of FIG. 1.

DESCRIPTION OF CERTAIN EMBODIMENTS

FIG. 1 shows an embodiment 20 of the invention that includes a chiller/heat pump 22. The chiller/heat pump 22 includes a metal-frame cabinet 24. The cabinet 24 is wrapped with stainless steel and includes a top surface 26. A residential-style five-ton air conditioning heat pump/condensing unit 28 is mounted to and supported by the top surface 26.

The cabinet 24 contains a sealed insulated tank 30 with fifty gallons of water. The tank 30 contains an all-copper bare tube evaporator main coil 32 immersed in the water 33 also contained by the tank 30. The immersion of the bare tube evaporator coil 32 in the tank 30 provides for a high extraction/rejection of BTUs. Referring to FIG. 2, the coil 32 includes four fluid lines: three 0.375-inch refrigerant lines 34 and one 0.75-inch recirculation line 36. The lines 34, 36 are attached (e.g., soldered/brazed) to each other. The immersion of the refrigeration lines 34 and recirculation line 36 in the water 33 in the tank 30 provides for high efficiency energy transfer. More specifically, any energy that cannot be removed or added by the small delta T of the water temperature in the recirculation lines 36 and the temperature of the refrigerant within the refrigeration line 34 can be added or removed from the water 33 within the tank 30. The water 33 stores this energy and it can be used when the refrigeration unit cycles off. The recirculation line 36 includes a water inlet 40 and a water outlet 42. The main coil 32 also includes a coil body 44, and a near-vertical tubing segment 46. The tubing segment 46 extends through the generally cylindrical space defined by the coil body 44.

The cabinet 24 also contains a 7.5-gallon plastic recirculating reserve tank 48, a circulating pump 50, and a refrigerant metering device 52. The embodiment 20 includes air handlers 60 connected to the chiller/heat pump 22 with flexible supply lines 62 and return lines 63. The supply lines 62 and return lines 63 may be, for example, garden-type water hoses. The flexible lines 62 and return lines 63 allows for the air handlers 60 to be moved easily and positioned to achieve the greatest potential effectiveness.

Each air handler 60 has a galvanized metal box 64. Two wheels 66 are mounted to the bottom of the box 64. Two feet 68 are mounted to the bottom of the box in the front. Each air handler box 64 contains a blower 70, an secondary evaporator coil 72, a supply connection 80 connected to a supply line 62, and a return connection 82 connected to a return line 63. The supply lines 62 are connected to a supply manifold 84. The return lines 63 are connected to a return manifold 86.

Operating During a Cooling Cycle

During a cooling cycle, the recirculating pump 50 moves water from the recirculating reserve tank 48 into the inlet 40 of the evaporator coil 32. The pumped water flows downward through the near-vertical tubing segment 46 to the bottom of the tank 30, which causes a natural convection flow of water 33 inside the tank 30. This obviates any need to use a circulating pump inside the tank 30 to move the warm water inside over the coils 32 for better heat transfer ability, making the temperature of the warm water inside the tank 30 an even temperature from top to bottom. This also provides a flash off of liquid refrigerant in the final portion of the coil 32 with the straight section 46 acting as an accumulator.

The volume of water 33 sealed within the insulated tank 30 is solely used for the purpose of heat transfer capacities and energy storage.

After reaching the bottom of the coil 32, water travels within the coil 32 up from the bottom. During this movement, thermal energy is absorbed from the water of the 50 gallons of water 33 and from the recirculation line 36, by the refrigerant lines 34, which are permanently attached to the exterior of the recirculation line 36. The chilled water leaves the evaporator coil 32 and travels into the supply manifold 84, which distributes the chilled water to the air handlers 60 through the supply lines 62. At the air handlers 60, the water enters through the supply connection 80 and moves into the coil 72.

Within each air handler 60, water enters the bottom of the coil 72 and travels upwards, absorbing thermal energy from the ambient air being moved through the air handler 60 by the blower 70. This creates a dehumidified, “cooler” discharge of air. Water then flows to the return connection 82 of the air handler 60, then through the return lines 63 and ultimately to the recirculating tank 48.

During a cooling cycle, high-pressure liquid refrigerant travels through the refrigerant lines 34 to the refrigerant metering device 52. After passing through the device 52, the refrigerant moves through the coil body 44 downward toward the bottom of the tank 30 through the refrigerant lines 34. As refrigerant moves through lines 34, the refrigerant absorbs thermal energy from both the water within the attached recirculation line 36 and the water 33 within the tank 30.

When the refrigerant reaches the bottom of the coil 32 and rises upwards through the near-vertical section, (where the heat of the returning water enters the coil 32) it allows the remaining refrigerant to flash to gas before it reaches the suction of the compressor of the condensing unit 28. The compressor then pumps the refrigerant back to a high-pressure liquid, which causes the refrigerant to reject the previously absorbed heat by means of the condensing coil, high pressure, and movement of air by the heat pump condensing unit fan within the unit 28. After the refrigerant passes completely through the condensing coil, it is back at the original point of refrigerant line out as sub-coolant refrigerant.

An embodiment of the system when operating in the cooling mode is capable of achieving 14 SEER (Seasonal Energy Efficiency Ratio) rating.

Operation During a Heating Cycle

The water flow path during a heating cycle is the same as the path during a cooling cycle. During a heating cycle, however, thermal energy is rejected into the stored water 33 within the tank 30 and into the recirculation line 36, which provides hot water to the coil 72 at the air handlers.

The refrigerant line 34 from the unit 28 becomes a hot gas line, thus using the immersed coil 32 as a condenser to reject thermal energy absorbed by the air passing through the condensing unit 28. Heat transfer occurs in reverse order inside the tank 30 from the previous explanation of the cooling mode operation.

Within each air handler 60, water enters the bottom of the coil 72 and travels upwards, rejecting thermal energy into the ambient air being moved through the air handler 60 by the blower 70. This creates a “warmer” discharge of air. Water then flows to the return connection 82 of the air handler 60, then through the return lines 63 and ultimately to the recirculating tank 48.

When the water 33 within the energy storage tank 30 reaches approximately 120° F., the refrigeration unit 28 cycles off. The water 33 provides adequate absorption/rejection of thermal energy (approximately 11,000 BTUs) from the recirculation line 36 to continue to provide desirable output temperatures by the air handlers 60 into the desired spaces.

An embodiment of the system operating in the heating mode is capable of achieving 3.5 COP (coefficient of performance).

The present invention is described above in terms of a preferred illustrative embodiment of a specifically-described system. Those skilled in the art will recognize that alternative constructions of such an apparatus can be used in carrying out the present invention. Other aspects, features, and advantages of the present invention may be obtained from a study of this disclosure and the drawings, along with the appended claims. 

1. An air conditioning and heating system comprising: an insulated tank; a main coil within the insulated tank, the main coil having a recirculation line with a water inlet and a water outlet, and a refrigerant line attached to the recirculation line; a heat pump/condensing unit connected to the refrigerant line; a circulating pump having a pump inlet and a pump outlet, the pump outlet connected to the water inlet of the main coil; a second tank connected to the pump inlet; and at least one air handler connected to the main coil and the second tank, the at least one air handler having a box, a blower within the box, and a secondary coil within the box, the secondary coil having a supply inlet connected to the water outlet of the main coil and a return outlet connected to the second tank.
 2. The system of claim 1 wherein the insulated tank is sealed.
 3. The system of claim 1 further comprising a volume of water within the insulated tank.
 4. The system of claim 1 further comprising flexible lines interconnecting the return coil outlet and the second tank and interconnecting the supply inlet and the water outlet of the main coil.
 5. An air conditioning and heating system comprising: a main coil and a tank of water; the main coil having a refrigeration line and a recirculation line, wherein said refrigeration line is directly attached to the recirculation line; the main coil is immersed in the tank of water.
 6. An air conditioning and heating system comprising: at least one air handler, at least one flexible water line, and at least one air conditioning and heating unit; wherein the a air handler is connected to a air conditioning and heating unit by a flexible water line.
 7. A method of conditioning and heating air comprising the steps of: introducing water to a main coil immersed in tank of water wherein said main coil comprises at least one recirculating line directly attached to at least one refrigeration line; the water travels through the main coil, out of the main coil, and into a flexible supply line; the water travels though said flexible supply line into an air handler. 